Dual balloons for pulmonary vein isolation

Abstract

Various examples of an ablation end effector are shown and described with two balloons independently inflatable so that a distal balloon can be used to ensure stability of the second balloon for electrical ablation in a beating heart. Methods and techniques to operate the ablation end-effectors are also described.

We claim: 
     
         1 . A balloon type medical apparatus comprising:
 a tubular member extending from a proximal portion to a distal portion along a longitudinal axis;   an actuator shaft extending from inside the tubular member to an actuator shaft distal end;   a first balloon comprising a first balloon distal portion coupled to the actuator shaft distal end and a first balloon proximal portion coupled to a slidable coupler;   a second balloon comprising a second balloon proximal portion coupled to the tubular member and a second balloon distal portion coupled to the slidable coupler, in which the slidable coupler includes:
 a coupler body with an opening extending along the longitudinal axis through the coupler body, the opening configured to allow movement of the coupler body relative to the actuator shaft and provide a sealing fit between the coupler body with the actuator shaft. 
   
     
     
         2 . The apparatus of  claim 1 , in which the first balloon is connected to the actuator shaft distal end with a nose piece disposed over a distal end portion of the first balloon to capture the distal end portion of the balloon between the nose piece and the actuator shaft. 
     
     
         3 . The apparatus of  claim 1 , in which the first balloon is connected to the slidable coupler with a coupling ring disposed over a proximal end portion of the first balloon and the coupler body of the slidable coupler so that the proximal end portion of the first balloon is captured between the coupling ring and the coupler body. 
     
     
         4 . The apparatus of  claim 1 , in which a distal end portion of the second balloon is captured between a coupling ring and the coupler body. 
     
     
         5 . The apparatus of  claim 1 , in which at least one puller wire is connected to the coupler body so that when the at least one puller wire is retracted towards the proximal portion of the tubular member, the slidable coupler translates relative to the actuator shaft. 
     
     
         6 . The apparatus of  claim 5 , in which the at least one puller wire comprises two puller wires disposed diametrically with respect to the longitudinal axis. 
     
     
         7 . The apparatus of  claim 1 , in which that actuator shaft includes a first passage to allow insertion of a guide wire into the first passage and a second passage generally parallel with the first passage to allow fluid to flow through the second passage and exit through at least one peripheral port. 
     
     
         8 . The apparatus of  claim 1 , in which the actuator shaft includes a first passage to allow insertion of a guidewire, a second passage to provide fluid flow to enter the second balloon via a fluid port and a third passage to allow fluid flow to the first balloon. 
     
     
         9 . The apparatus of  claim 1 , in which the sealing fit comprises a solid lubricant coating disposed on an outer surface of the actuator shaft having a thickness greater than a difference of an outside diameter of the actuator shaft and an inside diameter of the coupler body. 
     
     
         10 . The apparatus of  claim 1 , in which the sealing fit comprises a solid lubricant coating disposed on an inside surface of the coupler body having a thickness greater than a difference of an outside diameter of the actuator shaft and an inside diameter of the coupler body. 
     
     
         11 . The apparatus of  claim 1 , in which the second balloon includes a plurality of electrodes disposed on an outer surface of the second balloon. 
     
     
         12 . The apparatus of  claim 1 , in which the first balloon includes a plurality of electrodes disposed on an outer surface of the first balloon. 
     
     
         13 . The apparatus of  claim 1 , in which the first balloon includes a plurality of electrodes disposed on an outer surface of the first balloon and the second balloon includes a plurality of electrodes disposed on an outer surface of the second balloon. 
     
     
         14 . The apparatus of  claim 1 , in which the actuator shaft includes a primary irrigation passage to deliver fluid to the second balloon. 
     
     
         15 . The apparatus of  claim 1 , in which the actuator shaft includes a secondary irrigation passage to deliver fluid to the first balloon independent of delivery of fluid to the second balloon. 
     
     
         16 . A method of operating a balloon end effector, the method comprising the steps of:
 providing an end effector including:
 a tubular member extending from a proximal portion to a distal portion along a longitudinal axis with an actuator shaft extending from inside the tubular member to an actuator shaft distal end, the actuator shaft having a plurality of fluid ports; 
 a first balloon comprising a first balloon distal portion coupled to the actuator shaft distal end and a first balloon proximal portion coupled to a slidable coupler;
 a second balloon comprising a second balloon proximal portion coupled to the tubular member and a second balloon distal portion coupled to the slidable coupler; 
 
 extending the actuator shaft in a distal direction to a maximum length of the actuator shaft relative to the tubular member; and 
 inflating the first balloon without inflating the second balloon; and 
 inflating the second balloon. 
   
     
     
         17 . The method of  claim 16  further comprising the step of increasing a second balloon outer diameter of the second balloon to a maximum outer diameter and decreasing a first balloon outer diameter of the first balloon by retraction of a coupler body relative to the tubular shaft. 
     
     
         18 . The method of  claim 16  further comprising the step of increasing a first balloon outer diameter to a maximum outer diameter by retraction, relative to the tubular shaft, of the actuator shaft along the longitudinal axis towards the proximal portion of the tubular shaft. 
     
     
         19 . The method of  claim 16 , wherein the second balloon comprises a plurality of electrodes disposed on an outer surface of the second balloon. 
     
     
         20 . The method of  claim 19  further comprising ablating tissue with the plurality of electrodes.